In the operation of railroads, grease or other friction modifiers are applied onto railroad rails, such as to the top of rails or gauge face of rails at curves, turnouts, switches, in some cases, the sections of the track immediately before a switch, and periodically spaced along the length of the track. Such lubricants and friction modifying materials can either reduce or increase the friction where necessary to improve train performance, reduce wheel squeal, reduce wear on both the rails and the train wheels, or a combination thereof. Devices and methods for applying friction modifying materials to top of rail or gauge face rail surfaces include, for example, US 2008/0223661; GB 2,446,949; U.S. Pat. Nos. 2,821,263; 5,348,120; 5,394,958; 6,009,978; 6,742,624; 7,121,383; WO 2010/033900; WO 2010/138819 (these documents are herein incorporated by reference).
Rails have a head portion, a base portion, and a web portion extending between the head portion and the base portion. The head portion defines an outer surface comprising a top surface a field facing surface, and a gauge face surface. Lubricant or other friction modifying material may be applied to the top of rail, gauge face surface, or to both surfaces, as these locations contact the train wheels. However, the material may not always reach the desired location which can reduce the efficacy of friction modification. The material may also be wasted by dripping or flowing to a location where it does not perform its function optimally. The presence of this waste friction modifying material can cause undesirable safety, maintenance, or environmental issues. Apparatus for application of material can be prone to clogging or otherwise being impaired in their performance due to an accumulation of dirt or other residue.